40 BIRD-SONGS ABOUT WORCESTER. 



perhaps, have been alluded to in one of 

 my former letters. The male is glossy- 

 black, with the exception of the head, 

 which is dark brown, and the female is 

 brown all over. The cow-bird, as his 

 name implies, is most abundant in the 

 fields and pastures among the grazing 

 herds of cattle. But the most remarkable 

 thing about this bird is that it builds no 

 nest of its own, but deposits its eggs 

 surreptitiously in other birds' nests. This 

 habit it shares exclusively, among all the 

 birds known to science, with the European 

 cuckoo, a bird with which, however, it is 

 no wise allied. Ornithologists have specu- 

 lated as to the explanation of this eccen- 

 tricity exhibited by these widely different 

 birds, but apparently in vain. 



Dr. Coues suggests that perhaps some- 

 time in the remote past some female cow- 

 bird, dilatory about the building of her 

 nest, hit upon this easy expedient as a 

 necessary makeshift, and that gradually 

 the obnoxious custom extended to the 

 whole tribe of cow-birds. The smaller 



